A transfer ratio variable steering device that variably controls a transfer ratio between a steering angle and an actual rudder angle is known, for example, as a variable gear ratio steering (VGRS) device. The transfer ratio variable steering device changes the transfer ratio by controlling the drive of actuator such as VGRS motor. JP 4609515 B2 (US 2011/0010052 A1) describes a drive control of a VGRS motor according to operating state of an assistant motor of an electric power steering equipment.
From an environmental viewpoint to reduce fuel consumption, an eco-run vehicle (Stop-Start Systems) is developed. When the eco-run vehicle stops or slows down, the engine is suspended. When the eco-run vehicle starts or accelerates, the engine is started by cranking with a starter. The “eco-run” means economy and ecology running. The eco-run vehicle is synonymous with an idling stop vehicle.